html,
body,
#app {
  height: 100%;
}
/* 清除所有元素的默认样式 */

html,
body,
div,
span,
applet,
object,
iframe,
h1,
h2,
h3,
h4,
h5,
h6,
p,
blockquote,
pre,
a,
abbr,
acronym,
address,
big,
cite,
code,
del,
dfn,
em,
img,
ins,
kbd,
q,
s,
samp,
small,
strike,
strong,
sub,
sup,
tt,
var,
b,
u,
i,
center,
dl,
dt,
dd,
ol,
ul,
li,
fieldset,
form,
label,
legend,
table,
caption,
tbody,
tfoot,
thead,
tr,
th,
td {
  margin: 0;

  padding: 0;

  border: 0;

  outline: 0;

  font-size: 100%;

  vertical-align: baseline;

  background: transparent;
}

/* 清除链接默认样式 */

a {
  text-decoration: none;

  color: inherit;
}

/* 清除列表默认样式 */

ul,
ol {
  list-style: none;
}

/* 清除图片默认边框 */

img {
  border: none;
}

/* 清除表格默认边框 */

table {
  border-collapse: collapse;

  border-spacing: 0;
}
